MySQL 8.0.31
Source Code Documentation
ha_blackhole.h
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15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License, version 2.0, for more details.
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21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
22
23#include <sys/types.h>
24
25#include "my_base.h"
26#include "my_inttypes.h"
27#include "sql/handler.h" /* handler */
28#include "sql/key.h"
29#include "sql/table.h" /* TABLE_SHARE */
30#include "thr_lock.h" /* THR_LOCK */
31
32class String;
33class THD;
34struct FT_INFO;
35namespace dd {
36class Table;
37}
38
39/*
40 Shared structure for correct LOCK operation
41*/
46 char table_name[1];
47};
48
49/*
50 Class definition for the blackhole storage engine
51 "Dumbest named feature ever"
52*/
53class ha_blackhole : public handler {
54 THR_LOCK_DATA lock; /* MySQL lock */
56
57 public:
58 ha_blackhole(handlerton *hton, TABLE_SHARE *table_arg);
59 ~ha_blackhole() override = default;
60 /* The name that will be used for display purposes */
61 const char *table_type() const override { return "BLACKHOLE"; }
63 return HA_KEY_ALG_BTREE;
64 }
65 bool is_index_algorithm_supported(enum ha_key_alg key_alg) const override {
66 return key_alg == HA_KEY_ALG_BTREE || key_alg == HA_KEY_ALG_RTREE;
67 }
68 ulonglong table_flags() const override {
73 }
74 ulong index_flags(uint inx, uint, bool) const override {
75 return ((table_share->key_info[inx].algorithm == HA_KEY_ALG_FULLTEXT)
76 ? 0
79 }
80 /* The following defines can be increased if necessary */
81#define BLACKHOLE_MAX_KEY 64 /* Max allowed keys */
82#define BLACKHOLE_MAX_KEY_SEG 16 /* Max segments for key */
83#define BLACKHOLE_MAX_KEY_LENGTH 3072 /* Keep compatible with innoDB */
84 uint max_supported_keys() const override { return BLACKHOLE_MAX_KEY; }
85 uint max_supported_key_length() const override {
87 }
89 [[maybe_unused]]) const override {
91 }
92 int open(const char *name, int mode, uint test_if_locked,
93 const dd::Table *table_def) override;
94 int close(void) override;
95 int rnd_init(bool scan) override;
96 int rnd_next(uchar *buf) override;
97 int rnd_pos(uchar *buf, uchar *pos) override;
98 int index_read_map(uchar *buf, const uchar *key, key_part_map keypart_map,
99 enum ha_rkey_function find_flag) override;
100 int index_read_idx_map(uchar *buf, uint idx, const uchar *key,
101 key_part_map keypart_map,
102 enum ha_rkey_function find_flag) override;
104 key_part_map keypart_map) override;
105 int index_next(uchar *buf) override;
106 int index_prev(uchar *buf) override;
107 int index_first(uchar *buf) override;
108 int index_last(uchar *buf) override;
109 void position(const uchar *record) override;
110 int info(uint flag) override;
111 int external_lock(THD *thd, int lock_type) override;
112 int create(const char *name, TABLE *table_arg, HA_CREATE_INFO *create_info,
113 dd::Table *table_def) override;
115 enum thr_lock_type lock_type) override;
116 FT_INFO *ft_init_ext(uint flags, uint inx, String *key) override;
117 int ft_init() override;
118
119 protected:
120 int ft_read(uchar *buf) override;
121
122 private:
123 int write_row(uchar *buf) override;
124 int update_row(const uchar *old_data, uchar *new_data) override;
125 int delete_row(const uchar *buf) override;
126};
app_data_ptr new_data(u_int n, char *val, cons_type consensus)
Using this class is fraught with peril, and you need to be very careful when doing so.
Definition: sql_string.h:166
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_class.h:922
Definition: table.h:46
Definition: ha_blackhole.h:53
bool is_index_algorithm_supported(enum ha_key_alg key_alg) const override
Check if SE supports specific key algorithm.
Definition: ha_blackhole.h:65
int index_read_map(uchar *buf, const uchar *key, key_part_map keypart_map, enum ha_rkey_function find_flag) override
Positions an index cursor to the index specified in the handle ('active_index').
Definition: ha_blackhole.cc:193
int index_prev(uchar *buf) override
Definition: ha_blackhole.cc:235
int external_lock(THD *thd, int lock_type) override
Is not invoked for non-transactional temporary tables.
Definition: ha_blackhole.cc:156
int rnd_next(uchar *buf) override
Definition: ha_blackhole.cc:126
int open(const char *name, int mode, uint test_if_locked, const dd::Table *table_def) override
Definition: ha_blackhole.cc:82
ulong index_flags(uint inx, uint, bool) const override
Definition: ha_blackhole.h:74
int ft_read(uchar *buf) override
Definition: ha_blackhole.cc:274
~ha_blackhole() override=default
int index_read_idx_map(uchar *buf, uint idx, const uchar *key, key_part_map keypart_map, enum ha_rkey_function find_flag) override
Positions an index cursor to the index specified in argument.
Definition: ha_blackhole.cc:205
int info(uint flag) override
General method to gather info from handler.
Definition: ha_blackhole.cc:148
st_blackhole_share * share
Definition: ha_blackhole.h:55
int write_row(uchar *buf) override
Write a row.
Definition: ha_blackhole.cc:102
void position(const uchar *record) override
Definition: ha_blackhole.cc:143
ulonglong table_flags() const override
Definition: ha_blackhole.h:68
int index_next(uchar *buf) override
Definition: ha_blackhole.cc:228
FT_INFO * ft_init_ext(uint flags, uint inx, String *key) override
Definition: ha_blackhole.cc:256
int close(void) override
Definition: ha_blackhole.cc:91
uint max_supported_key_length() const override
Definition: ha_blackhole.h:85
int delete_row(const uchar *buf) override
Definition: ha_blackhole.cc:114
THR_LOCK_DATA ** store_lock(THD *thd, THR_LOCK_DATA **to, enum thr_lock_type lock_type) override
Is not invoked for non-transactional temporary tables.
Definition: ha_blackhole.cc:161
const char * table_type() const override
The following can be called without an open handler.
Definition: ha_blackhole.h:61
int ft_init() override
Definition: ha_blackhole.cc:272
int index_first(uchar *buf) override
Definition: ha_blackhole.cc:242
THR_LOCK_DATA lock
Definition: ha_blackhole.h:54
uint max_supported_keys() const override
Definition: ha_blackhole.h:84
ha_blackhole(handlerton *hton, TABLE_SHARE *table_arg)
Definition: ha_blackhole.cc:79
int rnd_init(bool scan) override
rnd_init() can be called two times without rnd_end() in between (it only makes sense if scan=1).
Definition: ha_blackhole.cc:121
int index_last(uchar *buf) override
Definition: ha_blackhole.cc:249
int create(const char *name, TABLE *table_arg, HA_CREATE_INFO *create_info, dd::Table *table_def) override
Create table (implementation).
Definition: ha_blackhole.cc:97
uint max_supported_key_part_length(HA_CREATE_INFO *create_info) const override
Definition: ha_blackhole.h:88
int rnd_pos(uchar *buf, uchar *pos) override
Definition: ha_blackhole.cc:137
int index_read_last_map(uchar *buf, const uchar *key, key_part_map keypart_map) override
The following functions works like index_read, but it find the last row with the current key value or...
Definition: ha_blackhole.cc:217
enum ha_key_alg get_default_index_algorithm() const override
Get default key algorithm for SE.
Definition: ha_blackhole.h:62
int update_row(const uchar *old_data, uchar *new_data) override
Update a single row.
Definition: ha_blackhole.cc:107
The handler class is the interface for dynamically loadable storage engines.
Definition: handler.h:4354
TABLE_SHARE * table_share
Definition: handler.h:4361
A table definition from the master.
Definition: rpl_utility.h:247
char * pos
Definition: do_ctype.cc:76
#define BLACKHOLE_MAX_KEY
Definition: ha_blackhole.h:81
#define BLACKHOLE_MAX_KEY_LENGTH
Definition: ha_blackhole.h:83
static int flags[50]
Definition: hp_test1.cc:39
static int flag
Definition: hp_test1.cc:39
This file includes constants used by all storage engines.
ha_key_alg
Definition: my_base.h:96
@ HA_KEY_ALG_RTREE
Definition: my_base.h:107
@ HA_KEY_ALG_BTREE
Definition: my_base.h:106
@ HA_KEY_ALG_FULLTEXT
Definition: my_base.h:109
ha_rkey_function
Definition: my_base.h:77
ulong key_part_map
Definition: my_base.h:1006
Some integer typedefs for easier portability.
unsigned long long int ulonglong
Definition: my_inttypes.h:55
unsigned char uchar
Definition: my_inttypes.h:51
Definition: buf0block_hint.cc:29
The version of the current data dictionary table definitions.
Definition: dictionary_client.h:42
mode
Definition: file_handle.h:59
required string key
Definition: replication_asynchronous_connection_failover.proto:59
#define HA_BINLOG_ROW_CAPABLE
Definition: handler.h:338
#define HA_FILE_BASED
Definition: handler.h:323
#define HA_CAN_INDEX_BLOBS
Definition: handler.h:256
#define HA_READ_NEXT
Definition: handler.h:525
#define HA_KEYREAD_ONLY
Definition: handler.h:570
#define HA_READ_OUT_OF_SYNC
Definition: handler.h:423
#define HA_CAN_GEOMETRY
Definition: handler.h:227
#define HA_CAN_FULLTEXT
Definition: handler.h:304
#define HA_BINLOG_STMT_CAPABLE
Definition: handler.h:339
#define HA_CAN_SQL_HANDLER
Definition: handler.h:309
#define HA_READ_ORDER
Definition: handler.h:541
#define HA_READ_RANGE
Definition: handler.h:548
#define HA_AUTO_PART_KEY
Definition: handler.h:261
#define HA_NULL_IN_KEY
Definition: handler.h:244
#define HA_READ_PREV
Definition: handler.h:529
case opt name
Definition: sslopt-case.h:32
Definition: ft_global.h:71
Definition: handler.h:2987
This structure is shared between different table objects.
Definition: table.h:689
KEY * key_info
Definition: table.h:745
Definition: table.h:1396
Definition: thr_lock.h:123
Definition: thr_lock.h:138
handlerton is a singleton structure - one instance per storage engine - to provide access to storage ...
Definition: handler.h:2594
Definition: mi_test3.cc:54
Definition: ha_blackhole.h:42
uint table_name_length
Definition: ha_blackhole.h:45
char table_name[1]
Definition: ha_blackhole.h:46
uint use_count
Definition: ha_blackhole.h:44
THR_LOCK lock
Definition: ha_blackhole.h:43
thr_lock_type
Definition: thr_lock.h:50
unsigned int uint
Definition: uca-dump.cc:29